<template>
  <div>
    <fieldset class="box-model-container">
      <legend>盒模型</legend>
      <div class="box-model">
        这里是内容
      </div>
    </fieldset>
  </div>
</template>
<script>
export default {
  name: 'BoxModel'
}
</script>
<style>
.box-model{
  background-color: green; 
  border: 3em solid red;
  margin: 3em;
  padding: 2em;
  border-radius: 3em;  
}
.box-model-container{
  background-color: blue;
  border: solid 10px orange;
  border-top-right-radius: 50px;
}
</style>
